A known polycarbonate resin produced from 2,2-bis(4-hydroxyphenyl)propane (commonly named as bisphenol A), which has high transparency and excellent mechanical properties, has been used for various application such as an optical material and an electronic material. For instance, recently, the polycarbonate resin has been widely used for an electrophotographic photoreceptor.
Repeated operations such as corona electrification or contact electrification using a roller and a brush, toner development, transfer onto paper, cleaning and the like are applied on a surface of a photosensitive layer of the electrophotographic photoreceptor. At every operation, electrical and external forces are applied on the surface of the photosensitive layer. Accordingly, in order to maintain electrophotography image quality for a long period of time, the photosensitive layer provided on the surface of the electrophotographic photoreceptor is required to have durability against these external forces. Durability against surface wear and scratch by friction and surface deterioration due to corona electrification or contact electrification, active gas such as ozone during transfer and discharge is particularly required.
To meet such a demand, a polycarbonate resin, which has good compatibility with charge transport materials used for the photosensitive layer and good optical properties, has been used as a binder resin of the electrophotographic photoreceptor. However, such a typical polycarbonate resin produced from bisphenol A described above and 1,1-bis(4-hydroxyphenyl)cyclohexane (bisphenol Z) is insufficient to satisfy the above demand.
Accordingly, in order to solve the above problem, an electrophotographic photoreceptor containing a polycarbonate provided with a siloxane bond at a main chain or a terminal end has been suggested (see, for instance, Patent Documents 1 to 7).    Patent Document 1: JP-A-61-132954    Patent Document 2: JP-A-2-240655    Patent Document 3: Japanese Patent No. 2933435    Patent Document 4: JP-A-6-220181    Patent Document 5: JP-A-5-072753    Patent Document 6: Japanese Patent No. 3350617    Patent Document 7: WO2005/113638 (Japanese Patent Application No. 2004-150295)    Patent Document 8: Japanese Patent No. 3606074